The present invention relates to sanitary fixtures and more particularly a drive apparatus to be used in the shower box and/or for the water tonic-massage fixtures for moving automatically sponges or rotating rolls to have a tonic massage and/or to facilitate particularly the washing of body""s parts which can be hardly reached such as back.
Some Patent Applications in the name of the same Applicant are known and disclose water tonic-massage fixtures and massotherapy apparatus provided with water-driven means wherein the rotatable devices are vertically moved by floatation hydrosystems or gears and racks. Even if such equipments guarantee their operation by water-driven means or by low-voltage electrical devices with the maximum safety for the user, they have a complex construction with large overall dimensions, moreover their installation is difficult.
U.S. Pat. No. 4,339,833, U.S. Pat. No. 4,274,400, DE-U-2950063, D-U-9302933, U.S. Pat. No. 5,035,010, and GB-A-2231487 disclose various water-driven shower or bath apparatuses provided with means for automatically reversing the movement, but these are mechanically very complicated, or they waste a lot of water, or they require a pressurized water supply, or they need modifications to the existing plumbing and/or building works or they are very complicated in the installation.
One object of the present invention is to provide a water-driven apparatus that is compact and easy to be installed, and guarantees a regular movement with automatic reversal without stoppage.
A second object of the present invention is to provide a drive apparatus for regulating independently upper and lower limit stops, thus allowing the excursion of the movement to be regulated.
According to the invention this is accomplished by providing a drive apparatus comprising in combination a water-driven motor, a demultiplier, and a mechanism of the screw-nut screw type capable of reversing automatically the movement whenever the nut screw reaches a limit stop without stopping and/or reversing the direction of rotation of the screw.